An endless track is used in an undercarriage system of a variety of track-type machines, such as, tractors, excavators, and so on. These endless tracks include track links that are interconnected to one another by track bushings.
During operation, the track bushing may experience excessive loading. Different surfaces of the track bushing, for example, an inner diameter, end ring surfaces, and so on may require abrasion resistance with increased strength and toughness to endure loads that may be imposed on the track bushing. The track bushing is generally made of low or medium carbon steel. The track bushing is deep carburized, forming carbon layers to depths of approximately 3000 microns on surfaces of the track bushing. Further, the track bushing may undergo air cooling and re-heat hardening. Additionally, the track bushing may be tempered to produce the track bushing of desired hardness.
However, time taken for carburizing the track bushing by known processes may be significant, often taking approximately between 10 and 24 hours. Thus, the production of the track bushing may be a time consuming, laborious, and costly process.
U.S. Pat. No. 5,032,192 describes a production method for an endless track bushing wherein medium-carbon steel is selected as a bushing material, the bushing material is carburized, quench-hardened, and then tempered. In the quenching, the bushing material is induction-heated from an outside surface of the bushing material only.